Ordering number : ENA1824A LV8734V Bi-CMOS LSI PWM Constant-Current Control Stepping Motor Driver Overview The LV8734V is a 2-channel H-bridge driver IC that can switch a stepping motor driver, which is capable of micro-step drive and supports 2W 1-2 phase excitation, and two channels of a brushed motor driver, which supports forward, reverse, brake, and standby of a motor. It is ideally suited for driving brushed DC motors and stepping motors used in office equipment and amusement applications. Features • Single-channel PWM current control stepping motor driver (selectable with DC motor driver channel 2) incorporated. • BiCDMOS process IC • Low on resistance (upper side : 0.48Ω ; lower side : 0.32Ω ; total of upper and lower : 0.8Ω ; Ta = 25°C, IO = 1.5A) • Excitation mode can be set to 2-phase, 1-2 phase, W1-2 phase , or 2W1-2 phase • Excitation step proceeds only by step signal input • Motor current selectable in four steps • Output short-circuit protection circuit (selectable from latch-type or auto-reset-type) incorporated • Unusual condition warning output pins • Built-in thermal shutdown circuit • No control power supply required Specifications Absolute Maximum Ratings at Ta = 25°C Parameter Symbol Supply voltage VM max Output peak current IO peak Output current IO max Logic input voltage MONI/EMO input voltage Conditions Ratings Unit 36 tw ≤ 10ms, duty 20% V 1.75 A 1.5 A VIN max -0.3 to +6 V Vmo/Vemo -0.3 to +6 V Continued on next page. Any and all SANYO Semiconductor Co.,Ltd. products described or contained herein are, with regard to "standard application", intended for the use as general electronics equipment (home appliances, AV equipment, communication device, office equipment, industrial equipment etc.). The products mentioned herein shall not be intended for use for any "special application" (medical equipment whose purpose is to sustain life, aerospace instrument, nuclear control device, burning appliances, transportation machine, traffic signal system, safety equipment etc.) that shall require extremely high level of reliability and can directly threaten human lives in case of failure or malfunction of the product or may cause harm to human bodies, nor shall they grant any guarantee thereof. If you should intend to use our products for applications outside the standard applications of our customer who is considering such use and/or outside the scope of our intended standard applications, please consult with us prior to the intended use. If there is no consultation or inquiry before the intended use, our customer shall be solely responsible for the use. Specifications of any and all SANYO Semiconductor Co.,Ltd. products described or contained herein stipulate the performance, characteristics, and functions of the described products in the independent state, and are not guarantees of the performance, characteristics, and functions of the described products as mounted in the customer' s products or equipment. To verify symptoms and states that cannot be evaluated in an independent device, the customer should always evaluate and test devices mounted in the customer' s products or equipment. O2710 SY/90110 SY 20100804-S00004 No.A1824-1/26 LV8734V Continued from preceding page. Parameter Symbol Allowable power dissipation Pd max Operating temperature Storage temperature Conditions Ratings * Unit 3.25 W Topr -20 to +85 °C Tstg -55 to +150 °C * Specified circuit board : 90.0mm×90.0mm×1.6mm, glass epoxy 2-layer board, with backside mounting. Allowable Operating Ratings at Ta = 25°C Parameter Symbol Conditions Ratings Unit Supply voltage range VM 9 to 32 V Logic input voltage VIN 0 to 5.5 V VREF input voltage range VREF 0 to 3 V Electrical Characteristics at Ta = 25°C, VM = 24V, VREF = 1.5V Parameter Symbol Ratings Conditions min typ Unit max Standby mode current drain IMst ST = “L” 100 400 μA Current drain IM ST = “H”, OE = “L”, with no load 3.2 5 mA VREG5 output voltage Vreg5 IO = -1mA 4.5 5 5.5 V Thermal shutdown temperature TSD Design guarantee 150 180 200 °C Thermal hysteresis width ΔTSD Design guarantee °C 40 Motor driver Output on resistance Ronu IO = 1.5A, Upper-side on resistance 0.48 0.63 Ω Rond IO = 1.5A, Lower-side on resistance 0.32 0.42 Ω 50 μA 1.2 1.4 V Output leakage current IOleak Diode forward voltage VD Logic high-level input voltage VINH Logic low-level input voltage VINL Logic pin input current IINL VIN = 0.8V other OE/CMK pin IINH VIN = 5V OE / CMK pin input current ICMKL DM = “L”, OE/CMK = 0.8V ICMKH DM = “L”, OE/CMK = 5V ICMK DM = “H”, OE/CMK = 0V VtCMK DM = “H” Vtdac0_2W Step 0 (When initialized : channel 1 OE/CMK pin current LIMIT mask ID = -1.5A 2.0 V 0.8 V 4 8 12 μA 30 50 70 μA 4 8 12 μA 30 50 70 μA -32 -25 -18 μA 1.2 1.5 1.8 V 0.291 0.3 0.309 V threshold voltage. Current setting 2W1-2 phase comparator drive comparator level) threshold Vtdac1_2W Step 1 (Initial state+1) 0.285 0.294 0.303 V voltage Vtdac2_2W Step 2 (Initial state+2) 0.267 0.276 0.285 V Vtdac3_2W Step 3 (Initial state+3) 0.240 0.249 0.258 V Vtdac4_2W Step 4 (Initial state+4) 0.201 0.21 0.219 V Vtdac5_2W Step 5 (Initial state+5) 0.157 0.165 0.173 V Vtdac6_2W Step 6 (Initial state+6) 0.107 0.114 0.121 V (current step switching) W1-2 phase Vtdac7_2W Step 7 (Initial state+7) 0.053 0.06 0.067 V Vtdac0_W Step 0 (When initialized : channel 1 0.291 0.3 0.309 V Vtdac2_W Step 2 (Initial state+1) 0.267 0.276 0.285 V Vtdac4_W Step 4 (Initial state+2) 0.201 0.21 0.219 V drive 1-2 phase drive comparator level) Vtdac6_W Step 6 (Initial state+3) 0.107 0.114 0.121 V Vtdac0_H Step 0 (When initialized : channel 1 0.291 0.3 0.309 V Vtdac4_H Step 4 (Initial state+1) 0.201 0.21 0.219 V Vtdac4_F Step 4' (When initialized : channel 1 0.291 0.3 0.309 V comparator level) 2 phase drive comparator level) Continued on next page. No.A1824-2/26 LV8734V Continued from preceding page. Parameter Symbol Ratings Conditions min typ Unit max Current setting comparator Vtatt00 ATT1 = L, ATT2 = L 0.291 0.3 0.309 V threshold voltage Vtatt01 ATT1 = H, ATT2 = L 0.232 0.24 0.248 V Vtatt10 ATT1 = L, ATT2 = H 0.143 0.15 0.157 V 0.053 0.06 0.067 40 50 60 kHz 7 10 13 μA 0.8 1 1.2 V 400 mV (current attenuation rate switching) Vtatt11 ATT1 = H, ATT2 = H Chopping frequency Fchop Cchop = 200pF CHOP pin charge/discharge current Ichop Chopping oscillation circuit Vtup V threshold voltage VREF pin input current Iref VREF = 1.5V MONI pin saturation voltage Vsatmon Imoni = 1mA μA -0.5 Charge pump VG output voltage VG Rise time tONG Oscillator frequency Fosc 28 28.7 29.8 V 200 500 μS 90 125 150 kHz 400 mV 7 10 13 μA 0.8 1 1.2 V VG = 0.1μF, 0.1μF between CP1-CP2 ST= “H” → VG=VM+4V Output short-circuit protection EMO pin saturation voltage Vsatemo CEM pin charge current Icem CEM pin threshold voltage Vtcem Iemo = 1mA Package Dimensions unit : mm (typ) 3333 TOP VIEW SIDE VIEW BOTTOM VIEW 15.0 44 23 (3.5) 0.5 5.6 7.6 (4.7) 0.22 22 0.2 1.7MAX 0.65 SIDE VIEW 0.1 (1.5) 1 (0.68) SANYO : SSOP44K(275mil) No.A1824-3/26 LV8734V Allowable power dissipation, Pd max - W 4.0 Pd max - Ta *1 With components mounted on the exposed die-pad board *2 With no components mounted on the exposed die-pad board Two-layer circuit board 1 *1 3.25 3.0 Two-layer circuit board 2 *2 2.20 2.0 1.69 1.14 1.0 0 —20 0 20 40 60 80 100 Ambient temperature, Ta - C Substrate Specifications (Substrate recommended for operation of LV8734V) Size : 90mm × 90mm × 1.6mm (two-layer substrate [2S0P]) Material : Glass epoxy Copper wiring density : L1 = 85% / L2 = 90% L1 : Copper wiring pattern diagram L2 : Copper wiring pattern diagram Cautions 1) The data for the case with the Exposed Die-Pad substrate mounted shows the values when 90% or more of the Exposed Die-Pad is wet. 2) For the set design, employ the derating design with sufficient margin. Stresses to be derated include the voltage, current, junction temperature, power loss, and mechanical stresses such as vibration, impact, and tension. Accordingly, the design must ensure these stresses to be as low or small as possible. The guideline for ordinary derating is shown below : (1)Maximum value 80% or less for the voltage rating (2)Maximum value 80% or less for the current rating (3)Maximum value 80% or less for the temperature rating 3) After the set design, be sure to verify the design with the actual product. Confirm the solder joint state and verify also the reliability of solder joint for the Exposed Die-Pad, etc. Any void or deterioration, if observed in the solder joint of these parts, causes deteriorated thermal conduction, possibly resulting in thermal destruction of IC. No.A1824-4/26 LV8734V Pin Assignment VG 1 44 OUT1A VM 2 43 OUT1A CP2 3 42 PGND CP1 4 41 NC VREG5 5 40 NC ATT2 6 39 VM1 ATT1 7 38 VM1 EMO 8 37 RF1 CEM 9 36 RF1 EMM 10 35 OUT1B CHOP 11 34 OUT1B LV8734V MONI 12 33 OUT2A RST/BLK 13 32 OUT2A STEP/DC22 14 31 RF2 FR/DC21 15 30 RF2 MD2/DC12 16 29 VM2 MD1/DC11 17 28 VM2 DM 18 27 NC OE/CMK 19 26 NC ST 20 25 PGND VREF 21 24 OUT2B GND 22 23 OUT2B Top view No.A1824-5/26 MONI PGND VM GND VREF VREG5 + - LVS TSD + - CHOP Oscillation circuit Regulator ATT2 Attenuator (4 levels selectable) ST ATT1 Charge pump Output preamplifier stage RF1 OUT1B VM1 MD1/ DC11 VM2 OUT2A Output control logic + RF2 Current Limit Mask Current selection (2W1-2/ W1-2/1-2/2) OUT2B MD2/ FR/ STEP/ RST/ OE/ DM EMM DC12 DC21 DC22 BLK CMK + Current selection (2W1-2/ W1-2/1-2/2) OUT1A Output preamplifier stage VG Output preamplifier stage CP1 Output preamplifier stage CP2 CEM EMO LV8734V Block Diagram No.A1824-6/26 LV8734V Pin Functions Pin No. Pin Name Pin Functtion 6 ATT2 Motor holding current switching pin. 7 ATT1 Motor holding current switching pin. 10 EMM Output short-circuit protection mode Equivalent Circuit VREG5 switching pin. 13 RST/BLK 14 STEP/DC22 15 FR/DC21 RESET input pin (STM) / Blanking time switching pin (DCM). STEP signal input pin (STM) / Channel 2 output control input pin 2 (DCM). 10kΩ CW / CCW signal input pin (STM) / Channel 2 output control input pin 1 (DCM). 16 MD2/DC12 Excitation mode switching pin 2 (STM) / 100kΩ Channel 1 output control input pin 2 (DCM). 17 MD1/DC11 Excitation mode switching pin 1 (STM) / GND Channel 1 output control input pin 1 (DCM). 18 DM Drive mode (STM/DCM) switching pin. 20 ST Chip enable pin. VREG5 20kΩ 10kΩ 80kΩ GND 23, 24 OUT2B Channel 2 OUTB output pin. 25, 42 PGND Power system ground. 28, 29 VM2 Channel 2 motor power supply 30, 31 RF2 32, 33 OUT2A Channel 2 OUTA output pin. 34, 35 OUT1B Channel 1 OUTB output pin. 36, 37 RF1 Channel 1 current-sense resistor 38, 39 VM1 Channel 1 motor power supply pin. 43, 44 OUT1A Channel 1 OUTA output pin. 38 39 28 29 connection pin. Channel 2 current-sense resistor connection pin. 34 35 23 24 43 44 32 33 connection pin. 10kΩ 500Ω 25 42 500Ω 36 37 30 31 GND Continued on next page. No.A1824-7/26 LV8734V Continued from preceding page. Pin No. Pin Name Pin Functtion 1 VG Charge pump capacitor connection pin. 2 VM Motor power supply connection pin. 3 CP2 Charge pump capacitor connection pin. 4 CP1 Charge pump capacitor connection pin. Equivalent Circuit 2 4 3 1 VREG5 100Ω GND 21 VREF Constant current control reference voltage input pin. VREG5 500Ω GND 5 VREG5 Internal power supply capacitor connection pin. VM 2kΩ 78kΩ 26kΩ GND 8 EMO Output short-circuit state warning output pin. 12 MONI VREG5 Position detection monitor pin. GND Continued on next page. No.A1824-8/26 LV8734V Continued from preceding page. Pin No. 9 Pin Name CEM Pin Functtion Pin to connect the output short-circuit Equivalent Circuit VREG5 state detection time setting capacitor. GND 11 CHOP Chopping frequency setting capacitor connection pin. VREG5 500Ω 500Ω GND 19 OE/CMK Output enable signal input pin(STM) / Set capacitor connection pin of time of VREG5 current LIMIT mask(DCM). GND 22 26, 27 40, 41 GND Ground. NC No Connection (No internal connection to the IC) No.A1824-9/26 LV8734V Description of operation Input Pin Function The function to prevent including the turn from the input to the power supply is built into each input pin. Therefore, the current turns to the power supply even if power supply (VM) is turned off with the voltage impressed to the input pin and there is not crowding. 1. Chip enable function This IC is switched between standby and operating mode by setting the ST pin. In standby mode, the IC is set to power-save mode and all logic is reset. In addition, the internal regulator circuit and charge pump circuit do not operate in standby mode. ST Mode Internal regulator Charge pump Low or Open Standby mode Standby Standby High Operating mode Operating Operating 2. Drive mode switching pin function The IC drive mode is switched by setting the DM pin. In STM mode, stepping motor channel 1 can be controlled by the CLK-IN input. In DCM mode, DC motor channel 2 or stepping motor channel 1 can be controlled by parallel input. Stepping motor control using parallel input is 2-phase or 1-2 phase full torque. DM Drive mode Application Low or Open STM mode Stepping motor channel 1 (CLK-IN) High DCM mode DC motor channel 2 or stepping motor channel 1 (parallel) STM mode (DM = Low or Open) 1. STEP pin function Operating mode Input ST STP Low * Standby mode High Excitation step proceeds High Excitation step is kept 2. Excitation mode setting function MD1 Low MD2 Excitation mode Initial position Channel 1 Channel 2 Low 2 phase excitation 100% -100% High Low 1-2 phase excitation 100% 0% Low High W1-2 phase excitation 100% 0% High High 2W1-2 phase excitation 100% 0% This is the initial position of each excitation mode in the initial state after power-on and when the counter is reset. 3. Position detection monitoring function The MONI position detection monitoring pin is of an open drian type. When the excitation position is in the initial position, the MONI output is placed in the ON state. (Refer to "Examples of current waveforms in each of the excitation modes.") No.A1824-10/26 LV8734V 4. Setting constant-current control reference current This IC is designed to automatically exercise PWM constant-current chopping control for the motor current by setting the output current. Based on the voltage input to the VREF pin and the resistance connected between RF and GND, the output current that is subject to the constant-current control is set using the calculation formula below : IOUT = (VREF/5)/RF resistance * The above setting is the output current at 100% of each excitation mode. The voltage input to the VREF pin can be switched to four-step settings depending on the statuses of the two inputs, ATT1 and ATT2. This is effective for reducing power consumption when motor holding current is supplied. Attenuation function for VREF input voltage ATT1 ATT2 Current setting reference voltage attenuation ratio Low Low 100% High Low 80% Low High 50% High High 20% The formula used to calculate the output current when using the function for attenuating the VREF input voltage is given below. IOUT = (VREF/5) × (attenuation ratio)/RF resistance Example : At VREF of 1.5V, a reference voltage setting of 100% [(ATT1, ATT2) = (L, L)] and an RF resistance of 0.5Ω, the output current is set as shown below. IOUT = 1.5V/5 × 100%/0.5Ω = 0.6A If, in this state, (ATT1, ATT2) is set to (H, H), IOUT will be as follows : IOUT = 0.6A × 20% = 120mA In this way, the output current is attenuated when the motor holding current is supplied so that power can be conserved. 5. Input timing TstepH TstepL STEP Tdh Tds (md1 step) (step md1) MD1 Tdh Tds (md2 step) (step md2) MD2 Tdh Tds (fr step) (step fr) FR TstepH/TstepL : Clock H/L pulse width (min 500ns) Tds : Data set-up time (min 500ns) Tdh : Data hold time (min 500ns) 6. Blanking time If, when exercising PWM constant-current chopping control over the motor current, the mode is switched from decay to charge, the recovery current of the parasitic diode may flow to the current sensing resistance, causing noise to be carried on the current sensing resistance pin, and this may result in erroneous detection. To prevent this erroneous detection, a blanking time is provided to prevent the noise occurring during mode switching from being received. During this time, the mode is not switched from charge to decay even if noise is carried on the current sensing resistance pin. In the stepping motor driver mode (DM = Low or Open) of this IC, the blanking time is fixed at approximately 1μs. In the DC motor driver mode (DM = High), the blanking time can be switched to one of two levels using the RST/BLK pin. (Refer to "Blanking time switching function.") No.A1824-11/26 LV8734V 7. Reset function (Only the STM mode. At DCM mode BLK pin : It operates as a switch function of the time of the bran king. Refer to (Blanking time switching function)) RST Operating mode Low Normal operation High Reset state RST RESET STEP MONI 1ch output 0% 2ch output Initial state When the RST pin is set to High, the excitation position of the output is forcibly set to the initial state, and the MONI output is placed in the ON state. When RST is then set to Low, the excitation position is advanced by the next STEP input. 8. Output enable function (Only the STM mode. At DCM mode CMK pin : It operates as current LIMIT mask function. Refer to (Current limit reference voltage setting function)) OE Operating mode Low Output ON High Output OFF OE Power save mode STEP MONI 1ch output 0% 2ch output Output is high-impedance When the OE pin is set High, the output is forced OFF and goes to high impedance. However, the internal logic circuits are operating, so the excitation position proceeds when the STEP signal is input. Therefore, when OE is returned to Low, the output level conforms to the excitation position proceeded by the STEP input. No.A1824-12/26 LV8734V 9. Forward/reverse switching function FR Operating mode Low Clockwise (CW) High Counter-clockwise (CCW) FR CW mode CCW mode CW mode STEP Excitation position (1) (2) (3) (4) (5) (6) (5) (4) (3) (4) (5) 1ch output 2ch output The internal D/A converter proceeds by one bit at the rising edge of the input STEP pulse. In addition, CW and CCW mode are switched by setting the FR pin. In CW mode, the channel 2 current phase is delayed by 90° relative to the channel 1 current. In CCW mode, the channel 2 current phase is advanced by 90° relative to the channel 1 current. 10. Chopping frequency setting For constant-current control, this IC performs chopping operations at the frequency determined by the capacitor (Cchop) connected between the CHOP pin and GND. The chopping frequency is set as shown below by the capacitor (Cchop) connected between the CHOP pin and GND. Fchop = Ichop/ (Cchop × Vtchop × 2) (Hz) Ichop : Capacitor charge/discharge current, typ 10μA Vtchop : Charge/discharge hysteresis voltage (Vtup-Vtdown), typ 0.5V For instance, when Cchop is 200pF, the chopping frequency will be as follows : Fchop = 10μA/ (200pF × 0.5V × 2) = 50kHz No.A1824-13/26 LV8734V 11. Output current vector locus (one step is normalized to 90 degrees) 100.0 θ0 θ4' (2-phase) θ1 θ2 Channel 1 phase current ratio (%) θ3 θ4 66.7 θ5 θ6 33.3 θ7 θ8 0.0 0.0 33.3 66.7 100.0 Channel 2 current ratio (%) Setting current ration in each excitation mode STEP 2W1-2 phase (%) Channel 1 W1-2 phase (%) Channel 2 Channel 1 θ0 100 0 θ1 98 20 θ2 92 38 θ3 83 55 θ4 70 70 θ5 55 83 θ6 38 92 θ7 20 98 θ8 0 100 1-2 phase (%) Channel 2 Channel 1 100 0 92 38 70 70 38 92 0 100 2-phase (%) Channel 2 Channel 1 100 0 70 70 0 100 100 Channel 2 100 No.A1824-14/26 LV8734V 12. Typical current waveform in each excitation mode 2-phase excitation (CW mode) STEP MONI (%) 100 l1 0 -100 (%) 100 I2 0 -100 1-2 phase excitation (CW mode) STEP MONI (%) 100 I1 0 -100 (%) 100 I2 0 -100 No.A1824-15/26 LV8734V W1-2 phase excitation (CW mode) STEP MONI (%) 100 0 I1 -100 (%) 100 I2 0 -100 2W1-2 phase excitation (CW mode) STEP MONI (%) 100 50 I1 0 -50 -100 (%) 100 50 I2 0 -50 -100 No.A1824-16/26 LV8734V 13. Current control operation specification (Sine wave increasing direction) STEP Set current Set current Coil current Forced CHARGE section Current mode CHARGE SLOW FAST CHARGE SLOW FAST (Sine wave decreasing direction) STEP Set current Coil current Forced CHARGE section Current mode CHARGE SLOW FAST Set current Forced CHARGE section FAST CHARGE SLOW In each current mode, the operation sequence is as described below : • At rise of chopping frequency, the CHARGE mode begins. (In the time defined as the “blanking time,” the CHARGE mode is forced regardless of the magnitude of the coil current (ICOIL) and set current (IREF).) • The coil current (ICOIL) and set current (IREF) are compared in this blanking time. When (ICOIL < IREF) state exists ; The CHARGE mode up to ICOIL ≥ IREF, then followed by changeover to the SLOW DECAY mode, and finally by the FAST DECAY mode for approximately 1μs. When (ICOIL < IREF) state does not exist ; The FAST DECAY mode begins. The coil current is attenuated in the FAST DECAY mode till one cycle of chopping is over. Above operations are repeated. Normally, the SLOW (+FAST) DECAY mode continues in the sine wave increasing direction, then entering the FAST DECAY mode till the current is attenuated to the set level and followed by the SLOW DECAY mode. No.A1824-17/26 LV8734V DCM Mode (DM=High) 1. DCM mode output control logic Parallel input Mode Output DC11 (21) DC12 (22) OUT1 (2) A OUT1 (2) B Low Low OFF OFF Standby High Low High Low CW (Forward) Low High Low High CCW (Reverse) High High Low Low Brake 2. Blanking time switching function (Only the DCM mode. At STM mode RST pin : It operates as RESET function. Refer to (reset function)) BLK Blanking time Low 2μs High 3μs 3. Current limit reference voltage setting function By setting a current limit, this IC automatically exercises short braking control to ensure that when the motor current has reached this limit, the current will not exceed it. (Current limit control time chart) Set current Current mode Coil current Forced CHARGE section fchop Current mode CHARGE SLOW The limit current is set as calculated on the basis of the voltage input to the VREF pin and the resistance between the RF pin and GND using the formula given below. Ilimit = (VREF/5) /RF resistance The voltage applied to the VREF pin can be switched to any of the four setting levels depending on the statuses of the two inputs, ATT1 and ATT2. Function for attenuating VREF input voltage ATT1 ATT2 Current setting reference voltage attenuation ratio Low Low 100% High Low 80% Low High 50% High High 20% The formula used to calculate the output current when using the function for attenuating the VREF input voltage is given below. Ilimit = (VREF/5) × (attenuation ratio) /RF resistance Example : At VREF of 1.5V, a reference voltage setting of 100% [(ATT1, ATT2) = (L, L)] and an RF resistance of 0.5Ω, the output current is set as shown below. Ilimit = 1.5V/5 × 100%/0.5Ω = 0.6A If, in this state, (ATT1, ATT2) has been set to (H, H), Ilimit will be as follows : Ilimit = 0.6A × 20% = 120mA No.A1824-18/26 LV8734V 4. Current LIMIT mask function (Only the DCM mode. At STM mode OE pin : It operates as output enable function. Refer to (output enable function)) The mask can do current LIMIT function during the fixed time set with the CMK pin at the DCM mode. It is effective to make it not hang to the limiter by the start current of the motor to set current LIMIT low. The charge is begun, current LIMIT function is done to the CMK capacitor meanwhile when switching to forward/ reverse mode, and the mask is done. Afterwards, the mask is released when the voltage of the CMK pin reaches set voltage (typ 1.5V), and the current limit function works. When 2ch side begins forward (reverse) operation while the mask on 1ch side is operating, the CMK pin is discharged one degree up to a constant voltage, and begins charging again because the CMK pin becomes 2ch using combinedly. Meanwhile, 1ch side and 2ch side enter the state of the mask. 1ch operate brake forward forward brake forward 2ch operate brake brake brake forward brake 1.5V CMK (capacitor) 1ch current limit 2ch current limit 0.3V mask release release mask release release mask mask mask mask When the capacitor is not connected, the function of LIMIT in the current can be switched to operation/nonoperating state by the state of the input of the CMK pin. CMK Current LIMIT function “L” nonoperating “H” or OPEN operation 5. Current LIMIT mask time (Tcmk) The time of the mask of current LIMIT function can be set by connecting capacitor CCMK between CMK pin - GND. Decide the value of capacitor CCMK according to the following expressions. Mask time : TCMK TCMK ≈ -CCMK × R × 1n ( 1- VtCMK / (ICMK × R )) (sec) VtCMK : LIMIT mask threshold voltage typ. 1.5V ICMK : CMK pin charge current typ. 25μA R : Internal resistance typ. 100kΩ No.A1824-19/26 LV8734V 6. Typical current waveform in each excitation mode when stepping motor parallel input control 2-phase excitation (CW mode) DC11 DC12 DC21 DC22 (%) 100 I1 0 -100 (%) 100 I2 0 -100 1-2 phase excitation full torque (CW mode) DC11 DC12 DC21 DC22 (%) 100 l1 0 -100 (%) 100 l2 0 -100 No.A1824-20/26 LV8734V Output short-circuit protection function This IC incorporates an output short-circuit protection circuit that, when the output has been shorted by an event such as shorting to power or shorting to ground, sets the output to the standby mode and turns on the warning output in order to prevent the IC from being damaged. In the stepping motor driver (STM) mode (DM = Low), this function sets the output to the standby mode for both channels by detecting the short-circuiting in one of the channels. In the DC motor driver mode (DM = High), channels 1 and 2 operate independently. (Even if the output of channel 1 has been short-circuited, channel 2 will operate normally.) 1. Output short-circuit protection operation changeover function Changeover to the output short-circuit protection of IC is made by the setting of EMM pin. EMM State Low or Open Latch method High Auto reset method 2. Latch type In the latch mode, when the output current exceeds the detection current level, the output is turned OFF, and this state is held. The detection of the output short-circuited state by the IC causes the output short-circuit protection circuit to be activated. When the short-circuited state continues for the time of time set using the internal timer (approximately 2μs), the output in which the short-circuiting has been detected is first set to OFF. After this, the output is set to ON again as soon as the timer latch time (Tcem) described later has been exceeded, and if the short-circuited state is still detected, all the outputs of the channel concerned are switched to the standby mode, and this state is held. This state is released by setting ST to low. Output ON H-bridge output state Output ON Output OFF Standby state Threshold voltage CEM voltage Short-circuit detection state Short- Release circuit Short-circuit Internal counter 1st counter start 1st counter 1st counter stop start 1st counter end 2nd counter start 2nd counter end No.A1824-21/26 LV8734V 3. Auto reset type In the automatic reset mode, when the output current exceeds the detection current level, the output waveform changes to the switching waveform. As with the latch system, when the output short-circuited state is detected, the short-circuit protection circuit is activated. When the operation of the short-circuit detection circuit exceeds the timer latch time (Tcem) described later, the output is changed over to the standby mode and is reset to the ON mode again in 2ms (typ). In this event, if the overcurrent mode still continues, the switching mode described above is repeated until the overcurrent mode is canceled. 4. Unusual condition warning output pins (EMO, MONI) The LV8731V is provided with the EMO pin which notifies the CPU of an unusual condition if the protection circuit operates by detecting an unusual condition of the IC. This pin is of the open-drain output type and when an unusual condition is detected, the EMO output is placed in the ON (EMO = Low) state. In the DC motor driver mode (DM = High), the MONI pin also functions as a warning output pin. The functions of the EMO pin and MONI pin change as shown below depending on the state of the DM pin. When the DM is low (STM mode) : EMO : Unusual condition warning output pin MONI : Excitation initial position detection monitoring When the DM is high (DCM) mode) : EMO : Channel 1 warning output pin MONI : Channel 2 warning output pin Furthermore, the EMO (MONI) pin is placed in the ON state when one of the following conditions occurs. 1. Shorting-to-power, shorting-to-ground, or shorting-to-load occurs at the output pin and the output short-circuit protection circuit is activated. 2. The IC junction temperature rises and the thermal protection circuit is activated. Unusual condition DM = L (STM mode) DM = H (DCM mode) EMO MONI EMO MONI Channel 1 short-circuit detected ON - ON - Channel 2 short-circuit detected ON - - ON Overheating condition detected ON - ON ON 5. Timer latch time (Tcem) The time taken for the output to be set to OFF when the output has been short-circuited can be set using capacitor Ccem, connected between the CEM pin and GND. The value of capacitor Ccem is determined by the formula given below. Timer latch : Tcem Tcem ≈ Ccem × Vtcem/Icem [sec] Vtcem : Comparator threshold voltage, typ 1V Icem : CEM pin charge current, typ 10μA Overheating protection function The overheating protection circuit is built into, and the output is turned off when junction temperature Tj exceeds 180°C, and the abnormal state warning output is turned on at the same time. The value of hysteresis and when it falls, the temperature drives the output again (automatic restoration). The overheating protection circuit doesn't secure protection and the destruction prevention of the set because it becomes operation by the area where ratings Tjmax=150°C of the junction temperature was exceeded. TSD = 180°C (typ) ΔTSD = 40°C (typ) No.A1824-22/26 LV8734V Charge Pump Circuit When the ST pin is set High, the charge pump circuit operates and the VG pin voltage is boosted from the VM voltage to the VM + VREG5 voltage. Because the output is not turned on if VM+4V or more is not pressured, the voltage of the VG pin recommends the drive of the motor to put the time of tONG or more, and to begin. ST VG pin voltage VM+VREG5 VM+4V VM tONG VG Pin Voltage Schematic View No.A1824-23/26 LV8734V Application Circuit Example • Stepping motor driver circuit (DM = Low) Short-circuit state detection monitor 100pF Position detection monitor Clock input Logic input OUT1A 44 2 VM OUT1A 43 3 CP2 PGND 42 4 CP1 NC 41 5 VREG5 NC 40 6 ATT2 VM1 39 7 ATT1 VM1 38 8 EMO RF1 37 9 CEM RF1 36 10 EMM OUT1B 35 11 CHOP 12 MONI 13 RST/BLK 1.0V 24V + - OUT1B 34 OUT2A 33 M OUT2A 32 14 STEP/DC22 RF2 31 15 FR/DC21 RF2 30 16 MD2/DC12 VM2 29 17 MD1/DC11 VM2 28 18 DM NC 27 19 OE/CMK NC 26 20 ST - + LV8734V 180pF 1 VG PGND 25 21 VREF OUT2B 24 22 GND OUT2B 23 The formulae for setting the constants in the examples of the application circuits above are as follows : Constant current (100%) setting When VREF = 1.0V IOUT = VREF/5/RF resistance = 1.0V/5/0.22Ω = 0.91A Chopping frequency setting Fchop = Ichop/ (Cchop × Vtchop × 2) = 10μA/ (180pF × 0.5V × 2) = 55kHz Timer latch time when the output is short-circuited Tcem = Ccem × Vtcem/Icem = 100pF × 1V/10μA = 10μs No.A1824-24/26 LV8734V • DC motor driver circuit (DM = High, and the current limit function is in use.) Channel 1 short-circuit state detection monitor 100pF Channel 2 position detection monitor OUT1A 44 2 VM OUT1A 43 3 CP2 PGND 42 4 CP1 NC 41 5 VREG5 NC 40 6 ATT2 VM1 39 7 ATT1 VM1 38 8 EMO RF1 37 9 CEM RF1 36 10 EMM OUT1B 35 11 CHOP 12 MONI LV8734V 180pF 1 VG 13 RST/BLK 24V + - M OUT1B 34 OUT2A 33 OUT2A 32 14 STEP/DC22 RF2 31 15 FR/DC21 RF2 30 16 MD2/DC12 VM2 29 17 MD1/DC11 VM2 28 M Logic input 18 DM NC 27 19 OE/CMK NC 26 20 ST - + PGND 25 21 VREF OUT2B 24 22 GND OUT2B 23 1.0V The formulae for setting the constants in the examples of the application circuits above are as follows : Constant current limit (100%) setting When VREF = 1.0V Ilimit = VREF/5/RF resistance = 1.0V/5/0.22Ω = 0.91A Chopping frequency setting Fchop = Ichop/ (Cchop × Vtchop × 2) = 10μA/ (180pF × 0.5V × 2) = 55kHz Timer latch time when the output is short-circuited Tcem = Ccem × Vtcem/Icem = 100pF × 1V/10μA = 10μs No.A1824-25/26 LV8734V SANYO Semiconductor Co.,Ltd. assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all SANYO Semiconductor Co.,Ltd. products described or contained herein. SANYO Semiconductor Co.,Ltd. strives to supply high-quality high-reliability products, however, any and all semiconductor products fail or malfunction with some probability. It is possible that these probabilistic failures or malfunction could give rise to accidents or events that could endanger human lives, trouble that could give rise to smoke or fire, or accidents that could cause damage to other property. When designing equipment, adopt safety measures so that these kinds of accidents or events cannot occur. Such measures include but are not limited to protective circuits and error prevention circuits for safe design, redundant design, and structural design. In the event that any or all SANYO Semiconductor Co.,Ltd. products described or contained herein are controlled under any of applicable local export control laws and regulations, such products may require the export license from the authorities concerned in accordance with the above law. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or any information storage or retrieval system, or otherwise, without the prior written consent of SANYO Semiconductor Co.,Ltd. Any and all information described or contained herein are subject to change without notice due to product/technology improvement, etc. When designing equipment, refer to the "Delivery Specification" for the SANYO Semiconductor Co.,Ltd. product that you intend to use. Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. Upon using the technical information or products described herein, neither warranty nor license shall be granted with regard to intellectual property rights or any other rights of SANYO Semiconductor Co.,Ltd. or any third party. SANYO Semiconductor Co.,Ltd. shall not be liable for any claim or suits with regard to a third party's intellctual property rights which has resulted from the use of the technical information and products mentioned above. This catalog provides information as of October, 2010. Specifications and information herein are subject to change without notice. PS No.A1824-26/26